Preoperative and Postoperative Factors Affecting Functional Success in Anatomically Successful Retinal Detachment Surgery

Mehmet Eren Guner(Mehmet Eren Guner ),Melis Kabaalioglu Guner(Melis Kabaalioglu Guner ),Zafer Cebeci3,Nur Kır(Zafer Cebeci3,Nur Kır ) 대한안과학회 2022 Korean Journal of Ophthalmology Vol.36 No.6

Purpose: To investigate preoperative and postoperative factors affecting functional success in anatomically successful retinal detachment surgery. Methods: Seventy-five eyes of 75 patients with rhegmatogenous retinal detachment who underwent anatomically successful surgery from 2014 to 2019 with more than 1 year follow-up were included in the study. Demographic characteristics, ocular examination findings, preoperative and postoperative spectral domain optic coherence tomography images were retrospectively evaluated. Results: The mean age was 53.9 ± 17 years (range, 11–85 years). The mean follow-up period was 36.7 ± 16 months (range, 14–72 months). The mean best-corrected visual acuity of the patients before surgery was 1.35 ± 1.24 and at postoperative 12 months was 0.66 ± 0.5 logarithm of the minimum angle of resolution. Patients who were operated in 7 days of visual symptoms onset were found to have better visual acuity at the first and subsequent postoperative exams. Preoperative proliferative vitreoretinopathy, vitreous hemorrhage, and extent of retinal detachment were found to have a negative effect on functional success at 12 months. Regeneration of the outer retinal layers had a positive effect on visual acuity at 12 months but did not significantly increase visual acuity after 12 months. Multivariate analysis showed that preoperative external limiting membrane integrity was significantly associated with better functional outcomes. Conclusions: Early intervention, presence of preoperative external limiting membrane integrity, and restoration of postoperative outer retinal layers positively affected functional success. The presence of preoperative vitreous hemorrhage, preoperative proliferative vitreoretinopathy, and the extent of retinal detachment had a negative effect on prognosis at 12 months.

An Extended Constrained Total Least-Squares Method for the Identification of Genetic Networks from Noisy Measurements

Guner, Ugur,Jang, Hong,Realff, Matthew J.,Lee, Jay H. American Chemical Society 2015 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.54 No.43

<P>We address the system identification problem of genetic networks using noisy and correlated time series data of gene expression level measurements. Least-squares (LS) is a commonly used method for the parameter estimation in the network reconstruction problems. The LS algorithm implicitly assumes that the measurement noise is confined only to the dependent variables. However, a discrete time model for the genetic network systems will lead to serially correlated noise terms that appear in both the dependent and independent variables. A constrained total least-squares algorithm (CTLS) used in signal and image processing applications showed significant improvements in such an estimation problem over the LS and total least-squares (TLS) methods. In this paper, we propose an extended CTLS algorithm that estimates parameters for all the dependent variables simultaneously, instead of estimating them separately for each dependent variable, as in the original CTLS algorithm. In addition, the CTLS algorithm is further generalized to assign weights to the error terms according to the variances or covariances of the measurement noise. We demonstrate its improved performance over the original CTLS method, as well as the commonly used LS and TLS methods on a widely adopted artificial genetic network example, under a variety of noise conditions.</P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ie5b01418'>ACS Electronic Supporting Info</A></P>

Safe Discharge Criteria After Curative Gastrectomy for Gastric Cancer

Guner, Ali,Kim, Ki Yoon,Park, Sung Hyun,Cho, Minah,Kim, Yoo Min,Hyung, Woo Jin,Kim, Hyoung-Il The Korean Gastric Cancer Association 2022 Journal of gastric cancer Vol.22 No.-

Purpose: This study aimed to investigate the relationship between clinical and laboratory parameters and complication status to predict which patients can be safely discharged from the hospital on the third postoperative day (POD). Materials and Methods: Data from a prospectively maintained database of 2,110 consecutive patients with gastric adenocarcinoma who underwent curative surgery were reviewed. The third POD vital signs, laboratory data, and details of the course after surgery were collected. Patients with grade II or higher complications after the third POD were considered unsuitable for early discharge. The performance metrics were calculated for all algorithm parameters. The proposed algorithm was tested using a validation dataset of consecutive patients from the same center. Results: Of 1,438 patients in the study cohort, 142 (9.9%) were considered unsuitable for early discharge. C-reactive protein level, body temperature, pulse rate, and neutrophil count had good performance metrics and were determined to be independent prognostic factors. An algorithm consisting of these 4 parameters had a negative predictive value (NPV) of 95.9% (95% confidence interval [CI], 94.2-97.3), sensitivity of 80.3% (95% CI, 72.8-86.5), and specificity of 51.1% (95% CI, 48.3-53.8). Only 28 (1.9%) patients in the study cohort were classified as false negatives. In the validation dataset, the NPV was 93.7%, sensitivity was 66%, and 3.3% (17/512) of patients were classified as false negatives. Conclusions: Simple clinical and laboratory parameters obtained on the third POD can be used when making decisions regarding the safe early discharge of patients who underwent gastrectomy.

Safe Discharge Criteria After Curative Gastrectomy for Gastric Cancer

Guner Ali,Kim Ki Yoon,Park Sung Hyun,Cho Minah,Kim Yoo Min,Hyung Woo Jin,Kim Hyoung-Il 대한위암학회 2022 Journal of gastric cancer Vol.22 No.4

Purpose This study aimed to investigate the relationship between clinical and laboratory parameters and complication status to predict which patients can be safely discharged from the hospital on the third postoperative day (POD). Materials and Methods Data from a prospectively maintained database of 2,110 consecutive patients with gastric adenocarcinoma who underwent curative surgery were reviewed. The third POD vital signs, laboratory data, and details of the course after surgery were collected. Patients with grade II or higher complications after the third POD were considered unsuitable for early discharge. The performance metrics were calculated for all algorithm parameters. The proposed algorithm was tested using a validation dataset of consecutive patients from the same center. Results Of 1,438 patients in the study cohort, 142 (9.9%) were considered unsuitable for early discharge. C-reactive protein level, body temperature, pulse rate, and neutrophil count had good performance metrics and were determined to be independent prognostic factors. An algorithm consisting of these 4 parameters had a negative predictive value (NPV) of 95.9% (95% confidence interval [CI], 94.2–97.3), sensitivity of 80.3% (95% CI, 72.8–86.5), and specificity of 51.1% (95% CI, 48.3–53.8). Only 28 (1.9%) patients in the study cohort were classified as false negatives. In the validation dataset, the NPV was 93.7%, sensitivity was 66%, and 3.3% (17/512) of patients were classified as false negatives. Conclusions Simple clinical and laboratory parameters obtained on the third POD can be used when making decisions regarding the safe early discharge of patients who underwent gastrectomy. Purpose This study aimed to investigate the relationship between clinical and laboratory parameters and complication status to predict which patients can be safely discharged from the hospital on the third postoperative day (POD). Materials and Methods Data from a prospectively maintained database of 2,110 consecutive patients with gastric adenocarcinoma who underwent curative surgery were reviewed. The third POD vital signs, laboratory data, and details of the course after surgery were collected. Patients with grade II or higher complications after the third POD were considered unsuitable for early discharge. The performance metrics were calculated for all algorithm parameters. The proposed algorithm was tested using a validation dataset of consecutive patients from the same center. Results Of 1,438 patients in the study cohort, 142 (9.9%) were considered unsuitable for early discharge. C-reactive protein level, body temperature, pulse rate, and neutrophil count had good performance metrics and were determined to be independent prognostic factors. An algorithm consisting of these 4 parameters had a negative predictive value (NPV) of 95.9% (95% confidence interval [CI], 94.2–97.3), sensitivity of 80.3% (95% CI, 72.8–86.5), and specificity of 51.1% (95% CI, 48.3–53.8). Only 28 (1.9%) patients in the study cohort were classified as false negatives. In the validation dataset, the NPV was 93.7%, sensitivity was 66%, and 3.3% (17/512) of patients were classified as false negatives. Conclusions Simple clinical and laboratory parameters obtained on the third POD can be used when making decisions regarding the safe early discharge of patients who underwent gastrectomy.

Biomarkers for Evaluating the Inflammation Status in Patients with Cancer

Guner, Ali,Kim, Hyoung-Il The Korean Gastric Cancer Association 2019 Journal of gastric cancer Vol.19 No.3

Inflammation can be a causative factor for carcinogenesis or can result from a consequence of cancer progression. Moreover, cancer therapeutic interventions can also induce an inflammatory response. Various inflammatory parameters are used to assess the inflammatory status during cancer treatment. It is important to select the most optimal biomarker among these parameters. Additionally, suitable biomarkers must be examined if there are no known parameters. We briefly reviewed the published literature for the use of inflammatory parameters in the treatment of patients with cancer. Most studies on inflammation evaluated the correlation between host characteristics, effect of interventions, and clinical outcomes. Additionally, the levels of C-reactive protein, albumin, lymphocytes, and platelets were the most commonly used laboratory parameters, either independently or in combination with other laboratory parameters and clinical characteristics. Furthermore, the immune parameters are classically examined using flow cytometry, immunohistochemical staining, and enzyme-linked immunosorbent assay techniques. However, gene expression profiling can aid in assessing the overall peri-interventional immune status. The checklists of guidelines, such as STAndards for Reporting of Diagnostic accuracy and REporting recommendations for tumor MARKer prognostic studies should be considered when designing studies to investigate the inflammatory parameters. Finally, the data should be interpreted after adjusting for clinically important variables, such as age and cancer stage.

Parameters for Predicting Surgical Outcomes for Gastric Cancer Patients: Simple Is Better Than Complex

Guner, Ali,Kim, Sang Yong,Yu, Jae Eun,Min, In Kyung,Roh, Yun Ho,Roh, Chulkyu,Seo, Won Jun,Cho, Minah,Choi, Seohee,Choi, Yoon Young,Son, Taeil,Cheong, Jae-Ho,Hyung, Woo Jin,Noh, Sung Hoon,Kim, Hyoung-I Springer - Society of Surgical Oncology 2018 Annals of surgical oncology Vol.25 No.11

Advantages of Splenic Hilar Lymph Node Dissection in Proximal Gastric Cancer Surgery

Guner, Ali,Hyung, Woo Jin The Korean Gastric Cancer Association 2020 Journal of gastric cancer Vol. No.

Gastrectomy with lymph node dissection remains the gold standard for curative treatment of gastric cancer. Dissection of splenic hilar lymph nodes has been included as a part of D2 lymph node dissection for proximal gastric cancer. Previously, pancreatico-splenectomy has been performed for dissecting splenic hilar lymph nodes, followed by pancreas-preserving splenectomy and spleen-preserving lymphadenectomy. However, the necessity of routine splenectomy or splenic hilar lymph node dissection has been under debate due to the increased morbidity caused by splenectomy and the poor prognostic feature of splenic hilar lymph node metastasis. In contrast, the relatively high incidence of splenic hilar lymph node metastasis, survival advantage, and therapeutic value of splenic hilar lymph node dissection in some patient subgroups, as well as the effective use of novel technologies, still supports the necessity and applicability of splenic hilar lymph node dissection. In this review, we aimed to evaluate the need for splenic hilar lymph node dissection and suggest the subgroup of patients with favorable outcomes.

Nozzle Designs in Powder-Based Direct Laser Deposition: A Review

Ahmet Guner,Prveen Bidare,Amaia Jiménez,Stefan Dimov,Khamis Essa 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.9

Laser-based Direct Energy Deposition (L-DED) is one of the most commonly employed metal additive manufacturing technologies. In L-DED, a laser beam is employed as a heat source to melt the metal powder that is deposited on a substrate layer by layer for the generation of a desired component. The powder is commonly fed through a nozzle into the molten pool by means of a carrier gas and therefore, a nozzle design that ensures optimal deposition of the material is of critical importance. Additionally, its design also affects the powder and gas flows that arise in the nozzle and during the deposition. This, in turn will affect the characteristics of the generated clad and the performance of the whole deposition. Therefore, an optimization of deposition nozzle geometry can be as important as the controlling of deposition process parameters in order to obtain best component qualities. In this context, the present review work is aimed at analysing the different nozzle designs employed in powder-based L-DED processes and the influence of different geometrical features and configurations on the resulting powder and gas flows. Concretely, the main characteristics of each design, their advantages and their possible shortcomings are analysed in detail. Additionally, a review of most relevant numerical models employed during the development of new and optimised nozzle designs are also addressed.

Advantages of Splenic Hilar Lymph Node Dissection in Proximal Gastric Cancer Surgery

Ali Guner,형우진 대한위암학회 2020 Journal of gastric cancer Vol. No.

Gastrectomy with lymph node dissection remains the gold standard for curative treatment of gastric cancer. Dissection of splenic hilar lymph nodes has been included as a part of D2 lymph node dissection for proximal gastric cancer. Previously, pancreatico-splenectomy has been performed for dissecting splenic hilar lymph nodes, followed by pancreas-preserving splenectomy and spleen-preserving lymphadenectomy. However, the necessity of routine splenectomy or splenic hilar lymph node dissection has been under debate due to the increased morbidity caused by splenectomy and the poor prognostic feature of splenic hilar lymph node metastasis. In contrast, the relatively high incidence of splenic hilar lymph node metastasis, survival advantage, and therapeutic value of splenic hilar lymph node dissection in some patient subgroups, as well as the effective use of novel technologies, still supports the necessity and applicability of splenic hilar lymph node dissection. In this review, we aimed to evaluate the need for splenic hilar lymph node dissection and suggest the subgroup of patients with favorable outcomes.

Biomarkers for Evaluating the Inflammation Status in Patients with Cancer

김형일,Ali Guner 대한위암학회 2019 Journal of gastric cancer Vol.19 No.3

Inflammation can be a causative factor for carcinogenesis or can result from a consequenceof cancer progression. Moreover, cancer therapeutic interventions can also induce aninflammatory response. Various inflammatory parameters are used to assess the inflammatorystatus during cancer treatment. It is important to select the most optimal biomarker amongthese parameters. Additionally, suitable biomarkers must be examined if there are noknown parameters. We briefly reviewed the published literature for the use of inflammatoryparameters in the treatment of patients with cancer. Most studies on inflammation evaluatedthe correlation between host characteristics, effect of interventions, and clinical outcomes. Additionally, the levels of C-reactive protein, albumin, lymphocytes, and platelets were themost commonly used laboratory parameters, either independently or in combination withother laboratory parameters and clinical characteristics. Furthermore, the immune parametersare classically examined using flow cytometry, immunohistochemical staining, and enzymelinkedimmunosorbent assay techniques. However, gene expression profiling can aid inassessing the overall peri-interventional immune status. The checklists of guidelines, such asSTAndards for Reporting of Diagnostic accuracy and REporting recommendations for tumorMARKer prognostic studies should be considered when designing studies to investigate theinflammatory parameters. Finally, the data should be interpreted after adjusting for clinicallyimportant variables, such as age and cancer stage.